Sodium alendronate is a biphosphonate compound represented by the following formula (formula 1): ##STR1##
Sodium alendronate inhibits bone resorption by osteoclast in vivo, and can be used as therapeutic agent for hypercalcemia, Paget's disease and osteoporosis (History of Medical Science, 165(9), pp. 674-678, 1993). In recent years, there have been note worthy cases where local accentuation of bone resorption is observed in such diseases as osteoarthritis (OA) and chronic articular rheumatism. Sodium alendronate is expected to provide an effective therapeutic agent for theses diseases